Chronic sinusitis: Temporal occurrence and relationship to medical claims for upper respiratory infections and allergic rhinitis

Background — Preliminary data suggest that upper respiratory infection diagnoses, but not allergic rhinitis diagnoses, are temporally related to chronic sinusitis diagnoses. Methods — We analysed monthly medical claims (ICD-9CM codes) for allergic rhinitis, upper respiratory infection and chronic sinusitis for 1990–1991 from three databases: the National Disease and Therapeutic Index (NDTI), the COMPASS Ohio Medicaid and the Blue Cross/Blue Shield of Minnesota (BC/BS-MN). We also assessed the timing and prevalence of upper respiratory infection, allergic rhinitis and chronic sinusitis in 200 cases from Ohio Medicaid. Results — We found statistically significant positive correlations between upper respiratory infection and chronic sinusitis in NDTI (r = 0.96), Ohio Medicaid (r = 0.95), and BC/BS-MN (r = 0.92), and statistically significant negative correlations between allergic rhinitis and chronic sinusitis in the NDTI (r = −0.55) and the BC/BS MN data (r = −0.57); the correlation between allergic rhinitis and chronic sinusitis in Ohio data was negative but not significant. Of the 200 sampled chronic sinusitis cases, 51.5% had upper respiratory infection with no allergic rhinitis-related diagnoses in the previous year; 12.0% had both upper respiratory infection- and allergic rhinitis-related diagnoses and 31% had neither. In the 90 days before chronic sinusitis, 74% of patients ages 10 had upper respiratory infection. Conclusions — In these populations, upper respiratory infection diagnoses were closer temporally to chronic sinusitis diagnoses than were allergic rhinitis diagnoses. In the 200 cases, upper respiratory infection was diagnosed more frequently than allergic rhinitis prior to chronic sinusitis. Although not indicative of a cause-effect relationship, these data suggest that upper respiratory infection may be a more common risk factor than allergic rhinitis for chronic sinusitis.